(1) Field of the Invention
This invention relates to a new apparatus for aiding in the communication of information to an audience when projected graphics are used by providing the lecturer with a simply controlled means for focusing attention to and enhancing the description of the significant portions of the projected graphics.
(2) Description of Prior Art
In the process of communicating information and concepts to an audience with the aid of projected graphics, a lecturer may wish to highlight certain portions of a projected image and will usually do so with the aid of a pointing stick or a projected arrow shaped cutout or, a ruby red laser beam. The use of the pointing stick is limited to relatively small and reachable screens and requires the lecturer to leave the lectern. Additionally, the pointing stick requires the lecturer to get close to the screen which usually results in obscuring the view of the projected image to some part of the audience. Another disadvantage of the pointing stick is that it forces the lecturer closer to the screen which can be visually uncomfortable for elderly speakers.
The second common method used by the lecturer to highlight the talk is the hand held arrow projector which is better than the pointing stick since it can be used from the lectern. However, it is very difficult to hold the arrow projector steady for extended periods of discussion, thus creating distractions to the audience from the subject matter of the lecture. All hand held, light projecting pointers suffer from hand tremor distraction problems including the ruby red laser pointer. Laser beam pointers also represent a serious health hazard if accidentally focused on the human eye. Manufacturers of these devices are careful to provide hazard warning labels to users but the potential for eye damage remains a serious limitation of its use.
None of the aforementioned devices include means for freeing the lecturer from support of the pointing or highlighting device, freezing the position of the pointing icon or, providing multiple pointing icons or multiple line highlighting overstrike as further aid to the lecturer in conveying ideas and concepts to the audience. It is readily understood that when a lecturer centers discussion around projected graphics of any complexity, an ability to utilize multiple pointing and highlighting techniques is a distinct advantage in conveying the full subject matter of the discussion. It should also be recognized that freeing the lecturer from support of the pointing or highlighting tool, as this invention does, enables better communication with the audience by allowing the lecturer to maintain audience eye contact otherwise lost by using the manually supported pointing means.
Patents have been issued for concepts of devices which generate a single highlighting point of light as controlled by the lecturer or synchronized with a recorded message such as described in U.S. Pat. No. 4,146,314 issued to S. Wilson in 1979 and U.S. Pat. No. 4,291,314 issued to S. Wilson in 1981. Although the Wilson patents overcome many of the sighted weaknesses of the hand held pointers, the art so described by these patents is not capable of full multigraphics overlay as is the apparatus of this invention. Also, the apparatus described by the Wilson patent is electromechanical wherein positional speed, repeatability and stability of the pointing spot are subject to the accuracy and repeatability limitations of motors, shaft encoders and servosystem errors, whereas none of these weaknesses and limitations apply to the apparatus of this invention since it does not requires servosystems to control the location of projected overlay graphic elements. Additionally, since the apparatus of the Wilson patent is electromechanical, it is subject to the generally poor reliability limits of complex mechanical mechanisms as compared to the significantly better reliability of properly designed solid state devices which are the major part of the apparatus of this invention.